JP2009208259A - Printing mask and manufacturing method of wiring substrate using this printing mask - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing mask which enables printing of a uniform amount of solder paste to a solder jointing pad formed on the surface of a wiring substrate, and can maintain a successful printability for a long time, without causing a significant viscosity change in the solder paste, even in case it is repeatedly used. <P>SOLUTION: This printing mask 10 is formed of a metal plate 1 having a squeegee slide surface F on which a squeegee slides scraping the solder paste and an opposite surface B which comes into contact with the wiring substrate. In addition, the printing mask 10 has as opening formed region 1A where many openings 2 through which a part of the solder paste scraped by the squeegee passes from the squeegee slide surface F to the opposite surface B side are collectively defined in a row corresponding to the solder jointing pad of the wiring substrate. Further, a rough surface region 1B with a more conspicuous surface roughness than the squeegee slide surface F of the other region, is partially formed on the squeegee slide surface F around the opening formed region 1A. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printing mask for printing a solder paste on a solder bonding pad arranged in a lattice pattern on the surface of a wiring board, and a method of manufacturing a wiring board using the same.

  In recent years, a wiring board used for mounting electronic components such as semiconductor integrated circuit elements is formed by alternately laminating a plurality of wiring conductors made of a glass base material and a thermosetting resin and copper foil or the like. There are used printed circuit boards and build-up boards formed by laminating a plurality of insulating layers made of thermosetting resin and filler and wiring conductors made of a copper plating layer on an insulating plate. And on the upper surface of such a printed circuit board or build-up circuit board, a large number of grid-like arrays are arranged to connect electrodes of electronic components such as semiconductor integrated circuit elements to the wiring conductor. The solder bonding pads are formed, and solder bumps for bonding the electrodes of the electronic components and the solder bonding pads are welded onto the solder bonding pads.

  In such a wiring board with solder bumps, electronic components such as semiconductor integrated circuit elements are placed on the wiring board such that their respective electrodes are in contact with the corresponding solder bumps. By heating with a heating device such as an electric furnace to melt the solder bump and joining the solder bump and the electrode of the electronic component, the electronic component is mounted on the wiring board.

  In addition, such a wiring board with solder bumps is connected to the wiring conductor on the surface of the insulating substrate having a plurality of wiring conductors on the inside and on the surface, and is arranged in a large number of circularly arranged in a lattice form. Solder bonding pads are formed, and then solder powder and solvent components on each solder bonding pad using a printing mask having an opening through which solder paste passes from the upper surface side to the lower surface side at a position corresponding to each solder bonding pad The solder paste containing the solder paste is applied by an amount corresponding to the solder bump by adopting a conventionally known screen printing method, and this is heated by reflow to melt the solder powder in the solder paste and onto the solder joint pad. It is manufactured by forming solder bumps.

  However, according to the conventional method for manufacturing a wiring board with solder bumps, when the solder paste is printed and applied onto each solder bonding pad, the outermost periphery (of the solder bonding pads arranged in a lattice pattern and arranged together) In particular, the amount of solder paste applied to the solder joint pads at the corners tends to be smaller than the amount applied to the inner solder joint pads. Therefore, when joining the electrode of the electronic component and the solder bonding pad via the solder bump, the solder amount of the outermost solder bump is insufficient and the strength of the solder bump becomes weak, There is a problem that it becomes impossible to firmly bond the solder bonding pad to the solder bump via the solder bump.

  Therefore, in Patent Document 1, a large number of solder joint pads to which electrodes of electronic components are connected are arranged in a grid on the upper surface of an insulating substrate having wiring conductors, and the center portion of the solder joint pads is arranged. A wiring board on which a solder resist layer having an opening for exposing the wiring is deposited, a bump forming opening arranged in a grid pattern at a position corresponding to each solder bonding pad, and an array of the bump forming openings A step of preparing a printing mask having a dummy opening formed on the outside with the same shape and the same arrangement interval as the bump forming opening, and printing on the solder bonding pad by using the printing mask. A step of printing and applying a dummy solder paste on the solder resist layer on the outer side of the solder paste for bump formation and the solder bonding pads; The solder in the solder paste and the solder in the dummy solder paste are heated and melted to form solder bumps joined to the solder joint pads and solder on the solder resist layer outside the solder joint pads. A method of manufacturing a wiring board with solder bumps has been proposed in which a step of forming a ball and a step of removing the solder ball are sequentially performed.

  However, according to the method for manufacturing a wiring board proposed in Patent Document 1, the solder in the dummy solder paste printed and applied onto the solder resist layer outside the array of the solder joint pads arranged in an aggregate is heated. When melting, the solder ball does not get wet with the solder resist layer, so it easily moves on the solder resist layer. Therefore, if the pitch of the solder bonding pads is narrow, for example, 200 μm or less, Even if the solder balls melted in step 1 move slightly due to the effects of vibration, impact, wind pressure, etc. that are received during the manufacturing process, they will contact and fuse with the adjacent solder bumps, resulting in the size of some solder bumps. Becomes extremely larger than other solder bumps, or adjacent solder bumps fuse together to cause an electrical short circuit. Electrode and solder bonding pad and the and the normal through the solder bumps can not be connected firmly situation is disadvantageously generated.

Patent Document 2 proposes a metal mask in which the squeegee sliding surface has a surface roughness Ra of 0.20 to 1.00 μm. However, the metal mask proposed in Patent Document 2 is formed by electroforming, and the entire surface of the squeegee sliding surface is a rough surface with a Ra of 0.20 to 1.00 μm. When the solder paste is printed using such a metal mask, the solder paste enters between the irregularities of the squeegee sliding surface, so that a thin solder paste film remains on the entire surface of the squeegee sliding surface after the squeegee sliding. Since the solvent component contained in the solder paste easily evaporates from the thin solder paste film remaining on the entire surface of the squeegee sliding surface, if the same solder paste is used and printing is repeated, the solvent in the solder paste The components are greatly reduced, and the viscosity of the solder paste increases within a short period of time, adversely affecting printability and inducing an unprecedented problem that good printing cannot be performed.
JP 2004-179363 A JP 7-276842 A

The present invention has been devised in view of such conventional problems, and an object of the present invention is to provide a uniform amount of solder on a large number of solder joint pads arranged in a lattice pattern on the surface of a wiring board. An object of the present invention is to provide a printing mask capable of printing a paste and capable of maintaining good printability for a long time without giving a large viscosity change to the solder paste even when the same solder paste is used repeatedly.
Another object of the present invention is to form solder bumps of uniform size on a large number of solder joint pads arranged in a grid on the surface of a wiring board without short-circuiting each other, thereby An object of the present invention is to provide a manufacturing method for obtaining a wiring board capable of normally and firmly connecting an electrode of an electronic component and a solder bonding pad via a solder bump.

  The printing mask of the present invention is used for printing a solder paste on a large number of solder bonding pads arranged in a grid on the surface of a wiring board, and a squeegee is slid while scraping the solder paste. A metal plate having a squeegee sliding surface and an opposite surface in contact with the wiring board, and an opening through which a part of the solder paste scraped by the squeegee passes from the squeegee sliding surface side to the opposite surface side. A printing mask having an opening formation region corresponding to the solder bonding pads and provided in a collective manner, wherein the surface of the squeegee sliding surface around the opening formation region is rougher than the squeegee sliding surface of other regions. A rough surface region having a rough thickness is partially formed.

  The method for manufacturing a wiring board according to the present invention is the method according to any one of claims 1 to 4, wherein the wiring board having a large number of solder bonding pads arranged in a lattice pattern on the surface has the surface side of the wiring board. The solder paste was printed on the solder joint pad by bringing the printing mask into contact with the squeegee and sliding the squeegee so that the squeegee passes through the opening formation region while scraping the solder paste. Then, the method includes a step of reflowing the solder paste to form solder bumps on the solder joint pads.

  According to the printing mask of the present invention, the squeegee sliding surface around the opening area in which a large number of openings are arranged corresponding to the solder bonding pads of the wiring board has a rough surface area with a surface roughness that is rougher than other areas. Therefore, when the squeegee slides on the sliding surface of the squeegee while scraping the solder paste, the flow resistance of the solder paste to be scratched increases in the rough surface region, thereby the outer peripheral portion of the opening forming region. As a result, the solder paste is rolled well, and the solder paste is satisfactorily supplied to the outermost solder joint pad among the solder joint pads, and a uniform amount of solder paste is printed on all the solder joint pads. Further, since the rough surface area is partially provided only around the opening forming area, the thin solder paste film remaining on the squeegee sliding surface after the squeegee slides has a narrow area only in the rough surface area. As a result, the amount of the solvent component that evaporates from the solder paste film can be greatly suppressed, and even if the same solder paste is used repeatedly, good printability is maintained for a long time without causing a large viscosity change in the solder paste. Can be maintained over time.

  Further, according to the method for manufacturing a wiring board of the present invention, the printing mask of the present invention is brought into contact with the surface side of the wiring board having a large number of solder bonding pads arranged in a grid on the surface. And printing the solder paste on the solder joint pad by sliding the squeegee on the sliding surface of the squeegee so that the squeegee passes through the opening forming region while scraping the solder paste. A uniform amount of solder paste is printed on the solder joint pads, and by reflowing this solder paste, uniform solder bumps are formed on all the solder joint pads, thereby making it possible to manufacture electronic components such as semiconductor integrated circuit elements. It is possible to provide a wiring board with solder bumps capable of normally and firmly connecting electrodes and solder bonding pads via solder bumps. .

  Next, the printing mask of the present invention will be described. FIG. 1 is a schematic top view showing an embodiment of the printing mask of the present invention, and FIG. 2 is a schematic sectional view taken along the line AA of the printing mask shown in FIG. FIG. 3 is a schematic top view of a wiring board on which a solder paste is printed using the printing mask of the present invention. 1 and 2, reference numeral 1 denotes a metal plate, 1A denotes an opening forming region, 1B denotes a rough surface region, 2 denotes an opening, F denotes a squeegee sliding surface, and B denotes an opposite surface. A mask 10 is constructed. In FIG. 3, 20 is a wiring board, and 24 is a solder bonding pad.

  The printing mask 10 of the present invention is used for printing a solder paste on the solder bonding pads 24 of the wiring board 20 shown in FIG. 3, and has a thickness of about 20 to 50 μm as shown in FIGS. The squeegee sliding surface F on which the squeegee slides while scraping the solder paste is provided on the upper surface side thereof, and the opposite surface B is in contact with the wiring board 20.

  The printing mask 10 has a large number of openings 2 penetrating from the sliding surface F to the opposite surface B of the metal plate 1 at positions corresponding to the solder bonding pads 24 of the wiring board 20. When the squeegee slides on the squeegee sliding surface F of the printing mask 10 while scraping the solder paste, a part of the solder paste passes through the opening 2 along the sliding surface F side. The solder paste is printed on the solder joint pad 24 by passing from the side to the opposite surface B side. The solder bonding pads 24 of the wiring board 20 have a diameter of about 50 to 200 μm, and a large number of grid-like arrays with a pitch of 100 to 250 μm are gathered and arranged on the surface of the wiring board 20. A large number of openings 2 corresponding to this and having a diameter of about 50 to 200 μm are gathered and provided. The print mask 10 corresponds to one or a plurality of wiring board 10 corresponding to the opening forming region 1A formed by gathering a large number of openings corresponding to the solder bonding pads 24 of the wiring board 20 as described above. Have. The opening 2 is formed in the metal plate 1 by using a photolithography technique.

  Further, the printing mask 10 of the present invention has a rough surface region 1B having a rougher surface roughness than the squeegee sliding surface F in other regions on the squeegee sliding surface F around the opening forming region 1A. The rough surface region 1B is intended to increase the flow resistance of the solder paste around the opening forming region 1A when the squeegee is slid on the squeegee sliding surface F while scraping the solder paste. As a result, rolling of the solder paste at the outer peripheral portion of the opening forming region 1A becomes good, and the solder paste is satisfactorily supplied to the outermost solder bonding pads 24 among the solder bonding pads 24 arranged in a large number. A uniform amount of solder paste is printed on all solder bonding pads 24. At this time, since the thin film of the solder paste does not remain in the region other than the rough surface region 1B on the squeegee sliding surface F, the amount of the solvent component evaporated from the solder paste can be greatly suppressed. Even when the same solder paste is used repeatedly, good printability can be maintained for a long time without giving a large viscosity change to the solder paste.

  When the arithmetic average roughness Ra of the rough surface region 1B is 0.3 μm or less, the flow resistance of the solder paste around the opening forming region 1A cannot be sufficiently increased, and as a result, the opening forming region 1A The solder paste does not roll well at the outer peripheral portion of the solder, and the amount of solder paste printed on the outermost solder joint pad 24 among the solder joint pads 24 arranged in a large number is likely to be insufficient. If the thickness exceeds 5 μm, a large amount of excess solder tends to remain on the printing mask. Therefore, the arithmetic average roughness Ra of the rough surface region 1B is preferably in the range of 0.3 to 5 μm. If the arithmetic surface roughness Ra of the region other than the rough surface region 1B on the squeegee sliding surface F exceeds 0.2 μm, when the squeegee slides on the squeegee sliding surface F while scraping the solder paste, A thin solder paste film tends to remain in a region other than the rough surface region 1B on the sliding surface F, and when the same solder paste is used and printing is repeated, evaporation of the solvent component from the solder paste increases. Within a short time, the viscosity of the solder paste is greatly increased, and the printability is lowered. Therefore, it is preferable that the arithmetic surface roughness Ra of the region other than the rough surface region 1B on the squeegee sliding surface F is 0.2 μm or less.

  Further, when the distance from the outermost peripheral opening 2 to the rough surface area 1B among the openings 2 arranged in the opening forming area 1A exceeds 250 μm, the flow resistance of the solder paste around the opening forming area 1A is sufficiently increased. As a result, the solder paste does not roll well in the outer peripheral portion of the opening formation region 1A, and the solder joint pads 24 arranged in a large number are arranged on the outermost solder joint pads 24. The amount of solder paste to be printed tends to be insufficient. Therefore, it is preferable that the distance from the outermost peripheral opening 2 to the rough surface area 1B among the openings 2 arranged in the opening forming area 1A is 250 μm or less.

  Furthermore, when the width of the rough surface region 1B is less than 100 μm, the flow resistance of the solder paste around the opening forming region 1A cannot be sufficiently increased, and as a result, the solder paste rolling around the outer periphery of the opening forming region 1A. The solder paste amount printed on the outermost solder joint pad 24 among the solder joint pads 24 arranged in a large number is likely to be insufficient, and the squeegee exceeds 5 μm. When the squeegee is slid on the sliding surface F while scraping the solder paste, a thin solder paste film is likely to remain in a large area on the rough surface region 1B, thereby printing using the same solder paste. Repeatedly, the evaporation of the solvent component from the solder paste increases, and the viscosity of the solder paste increases greatly within a short period of time, and the printability tends to decrease. The Therefore, the width of the rough surface region 1B is preferably in the range of 100 μm to 5 mm.

  In order to form the rough surface region 1B on the squeegee sliding surface F around the opening forming region 1A, it is only necessary to form irregularities with a dot or streak depth of 0.3 to 2 μm by laser processing. Or you may give an unevenness | corrugation by carrying out a chemical etching process or processing mechanically.

  Next, using the above-described printing mask 10 of the present invention, a solder paste is printed on the solder bonding pads 24 of the wiring board 20, and the wiring board 20 with solder bumps is manufactured by reflowing the solder paste. A method for manufacturing the substrate will be described. 4 to 6 are schematic cross-sectional views for each process for explaining the method for manufacturing a wiring board according to the present invention. In these drawings, 10 is a printing mask, 20 is a wiring board, 24 is a solder bonding pad, 31 is a squeegee, and 32 is a solder paste.

  First, as shown in FIG. 4, the above-described printing mask 10 and wiring board 20 of the present invention are prepared. In FIG. 4, only a portion corresponding to one wiring board 20 is extracted and shown, and the printing mask 10 may include a plurality of opening formation regions 1 </ b> A corresponding to the plurality of wiring boards 20, It is supported with a suitable tension on a frame-shaped metal frame (not shown).

  The wiring substrate 20 is a surface of the insulating plate 21a of the insulating substrate 21 in which a plurality of insulating layers 21b made of a thermosetting resin are laminated on the upper and lower surfaces of an insulating plate 21a made of glass fabric impregnated with a thermosetting resin, for example. A wiring conductor 22 made of copper foil or copper plating is disposed on the surface of each insulating layer 21b, and a solder resist layer 23 made of a thermosetting resin is further deposited on the outermost insulating layer 21b. Further, a mounting portion A on which an electronic component such as a semiconductor integrated circuit element is mounted is formed in the central portion of the upper surface of the insulating substrate 21, and the electrodes of the electronic component are electrically connected to the mounting portion A through solder bumps. A large number of solder bonding pads 24 to be connected are arranged in a grid.

  The insulating plate 21a is a core member in the wiring board 20, and is formed, for example, by impregnating a glass fabric in which glass fiber bundles are woven vertically and horizontally with a thermosetting resin such as an epoxy resin or a bismaleimide triazine resin. The insulating plate 21a has a thickness of about 0.3 to 1.5 mm, for example, and has a plurality of through holes 25 with a diameter of about 0.1 to 1 mm from the upper surface to the lower surface. A part of the wiring conductor 22 is attached to the upper and lower surfaces and the inner surface of each through hole 25, and the upper and lower wiring conductors 22 are electrically connected via the through hole 25.

  Such an insulating plate 21a is manufactured by thermally curing an insulating sheet in which a glass fabric is impregnated with an uncured thermosetting resin, and then drilling the insulating sheet from the upper surface to the lower surface. Note that the wiring conductors 22 on the upper and lower surfaces of the insulating plate 21a have a copper foil having a thickness of about 3 to 50 μm adhered to the entire upper and lower surfaces of the insulating sheet for the insulating plate 21a, and the copper foil is etched after the sheet is cured. By doing so, a predetermined pattern is formed. The wiring conductor 22 on the inner surface of the through hole 25 is provided with a copper plating film having a thickness of about 3 to 50 μm by electroless plating and electrolytic plating on the inner surface of the through hole 25 after the through hole 25 is provided in the insulating plate 21a. Formed by precipitation.

  Further, the insulating plate 21 a is filled with a hole filling resin 26 made of a thermosetting resin such as an epoxy resin or a bismaleimide triazine resin in the through hole 25. The hole-filling resin 26 is for making it possible to form the wiring conductor 22 and each insulating layer 21b directly above and below the through-hole 25 by closing the through-hole 25, and is an uncured paste-like thermosetting resin. Is filled in the through-hole 25 by a screen printing method, thermally cured, and then the upper and lower surfaces thereof are polished substantially flatly. In this example, two insulating layers 21b are laminated on the upper and lower surfaces of the insulating plate 21a including the hole filling resin 26, respectively.

  Each insulating layer 21b laminated on the upper and lower surfaces of the insulating plate 21a is made of a thermosetting resin such as an epoxy resin or a bismaleimide triazine resin, and each has a thickness of about 20 to 60 μm, and has a diameter from the upper surface to the lower surface of each layer. Has a plurality of through holes 27 of about 30 to 100 μm. Each of these insulating layers 21b is for providing an insulating interval for wiring the wiring conductors 22 with high density. A high-density wiring can be three-dimensionally formed by electrically connecting the upper wiring conductor 22 and the lower wiring conductor 22 through the through hole 27. Each such insulating layer 21b has an insulating film made of an uncured thermosetting resin having a thickness of about 20 to 60 μm attached to the upper and lower surfaces of the insulating plate 21a. 27, and the next insulating layer 21b is sequentially stacked thereon in the same manner. The wiring conductor 22 deposited in the surface of each insulating layer 21b and in the through hole 27 has a thickness of about 5 to 50 μm in the surface of each insulating layer 21b and in the through hole 27 every time each insulating layer 21b is formed. This copper plating film is formed by depositing it in a predetermined pattern by a pattern forming method such as a known semi-additive method.

  The solder bonding pads 24 formed on the mounting portion A on the upper surface of the insulating substrate 21 have a circular shape with a diameter of about 50 to 200 μm, and a large number of grid-like arrays with a pitch of 100 to 250 μm are formed in the region within the mounting portion A. Collectively arranged. Such a solder bonding pad 24 functions as a terminal portion for electrically connecting an electrode of an electronic component such as a semiconductor integrated circuit element to the wiring conductor 22, and is a wiring conductor formed on the uppermost insulating layer 21b. Part 22 is exposed in a circular opening 23 a having a diameter of 50 to 200 μm provided in the solder resist layer 23.

  The solder resist layer 23 functions as a dam member that protects the outermost wiring conductor 22 from the external environment and prevents an electrical short circuit between the solder bonding pads 24, and is uncured for the solder resist layer 23 having photosensitivity. The resin paste is applied onto the outermost insulating layer 21b using a roll coater method or a screen printing method, dried, and then exposed and developed to expose the central portion of the solder bonding pad 24. It is formed by forming 23a and then thermosetting it.

  Next, as shown in FIGS. 5A to 5C, the print mask 10 is placed on the upper surface of the wiring board 20, and the squeegee 31 is placed on the squeegee sliding surface F of the print mask 10, and the squeegee 31 is solder paste. A part of the solder paste 32 is embedded in each opening 2 by sliding the sheet 32 so as to pass through the opening forming region 1A, and then the print mask 10 is removed from the wiring board 20 to remove the wiring. A solder paste 32 is printed on the solder bonding pad 24 of the substrate 20. At this time, the printing mask 10 has a rough surface region 1B having a rougher surface roughness than the squeegee sliding surface F in the other regions on the squeegee sliding surface F around the opening forming region 1A. The rough surface region 1B increases the flow resistance of the solder paste 32 around the opening forming region 1A, thereby improving the rolling of the solder paste 32 on the outer periphery of the opening forming region 1A, and arranging a large number of them. The solder paste 32 is satisfactorily supplied to the outermost solder joint pads 24 among the solder joint pads 24 thus formed, and a uniform amount of the solder paste 32 is printed on all the solder joint pads 24. At this time, since the thin film of the solder paste 32 does not remain in the region other than the rough surface region 1B on the squeegee sliding surface F, the amount of the solvent component evaporated from the solder paste 32 can be greatly suppressed. Even if the same solder paste 32 is used repeatedly, good printability can be maintained for a long time without giving a large viscosity change to the solder paste 32.

  Finally, by reflowing the solder paste 32 printed on the solder bonding pad 24 of the wiring board 20, as shown in FIG. 6, the solder bump in which the solder bump 28 having a uniform size is formed on the solder bonding pad 24. A wiring board with a mark is completed. As described above, according to the manufacturing method of the present invention, the print mask 10 of the present invention is brought into contact with the upper surface of the wiring board 20 and the squeegee 31 is opened on the squeegee sliding surface F while the squeegee 31 scratches the solder paste 32. Since the solder paste 32 is printed on the solder joint pad 24 by sliding so as to pass through the formation region 1A, a uniform amount of the solder paste 32 is printed on each solder joint pad 24 of the wiring board 20, and this solder By reflowing the paste 32, solder bumps 28 having a uniform size are formed on all the solder bonding pads 24, whereby the electrodes of electronic components such as semiconductor integrated circuit elements and the solder bonding pads 24 are connected via the solder bumps 28. Thus, a wiring board with solder bumps that can be connected normally and firmly can be obtained.

It is a principal part schematic top view which shows the embodiment of the printing mask of this invention. It is a schematic sectional drawing in the AA cut line of the printing mask 10 shown in FIG. It is a schematic top view which shows the example of the wiring board by which a solder paste is printed using the printing mask of this invention. It is a schematic sectional drawing for demonstrating the manufacturing method of the wiring board of this invention. (A)-(c) is a schematic sectional drawing for demonstrating the manufacturing method of the wiring board of this invention. It is a schematic sectional drawing for demonstrating the manufacturing method of the wiring board of this invention.

Explanation of symbols

1: Metal plate 1A: Opening formation region 1B: Rough surface region 2: Opening 10: Print mask 20: Wiring substrate 24: Solder bonding pad 31: Squeegee 32: Solder paste F: Squeegee sliding surface B: Opposite surface

Claims (5)

  A squeegee sliding surface that is used to print solder paste on a large number of solder bonding pads arranged in a grid on the surface of a wiring board, and the squeegee slides while scraping the solder paste, and the wiring An opening through which a part of the solder paste scraped by the squeegee passes from the squeegee sliding surface side to the opposite surface side corresponds to the solder bonding pad. In addition, a printing mask having an opening forming region provided in a large number, wherein a rough surface region having a rougher surface roughness than a squeegee sliding surface in another region is formed on the squeegee sliding surface around the opening forming region. A printing mask characterized by being partially formed.   The surface roughness of the rough surface region is 0.3 to 5 μm in arithmetic average roughness Ra, and the surface roughness of the other region is 0.2 μm or less in arithmetic average roughness Ra. The printing mask according to claim 1.   The printing mask according to claim 1 or 2, wherein a distance from the outermost peripheral opening to the rough surface area among the openings provided in the opening forming area is 250 µm or less.   The printing mask according to claim 1, wherein a width of the rough surface region is 100 μm to 5 mm.   The squeegee slide and the printing mask according to any one of claims 1 to 4 are brought into contact with the surface side of a wiring board having a large number of solder bonding pads arranged in a grid on the surface. The solder paste is printed on the solder joint pad by sliding a squeegee on the moving surface so that the squeegee passes through the opening forming region while scraping the solder paste, and then reflowing the solder paste, A method of manufacturing a wiring board comprising a step of forming solder bumps on a bonding pad.

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